Background: The ideal force-delivery system must: provide optimal tooth moving forces that elicit the desired effects, be comfortable and hygienic for the patient, require minimal operator manipulation and patient cooperation and provide rapid tooth movement with minimal mobility during orthodontic therapy, the elastomeric chains have the greatest potential to fulfill these requirements. Materials and Methods: This in vitro study was designed to determine the effect of three different mechanisms for canine retraction : (6-3 , 6-5-3 and chain loop ) on the load relaxation behavior of three types of elastomeric chains : (maximum clear , maximum silver and extreme silver) from the same company (Ortho Technology company) with two different brand configurations: closed loop and open (short filament) chains under effect of time at (zero time, 24hr., 7, 14 , 21 and 28 days) in artificial saliva. Results: Statistical analysis showed that there was a highly significant difference in the mean percentage force decay for the three different mechanisms (P? 0.001).For all the three types, the 6-3 mechanism had the smallest mean percentage force decay. There was a highly significant difference in the mean percentage force decay for the different types (P? 0.001). For all three mechanisms, extreme silver elastomeric chains had the smallest percentage force decay while maximum silver elastomeric chains had the highest percentage force decay. Conclusion: This study illustrated that for all the three types of elastomeric chains, the (6-3) mechanism had the smallest mean percentage force decay. This finding suggests that it may be most efficient to retract a canine utilizing elastomeric chain directly from the molar hook to the canine bracket. The chain loop mechanism may not be indicated for space closure in vivo due to the excessive physiological force values involved with this mechanism.
This study proposes a mathematical approach and numerical experiment for a simple solution of cardiac blood flow to the heart's blood vessels. A mathematical model of human blood flow through arterial branches was studied and calculated using the Navier-Stokes partial differential equation with finite element analysis (FEA) approach. Furthermore, FEA is applied to the steady flow of two-dimensional viscous liquids through different geometries. The validity of the computational method is determined by comparing numerical experiments with the results of the analysis of different functions. Numerical analysis showed that the highest blood flow velocity of 1.22 cm/s occurred in the center of the vessel which tends to be laminar and is influe
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This study was conducted to determine the effect of vitamin A ( 10 mg/kg ) on avearage testis weight and sexual glands ( Prostate and Seminal Vesicle ) for albino male mice treated with Hexavalent chromium ( 1000 ppm ) .The current study 40 mice were divided into fife groups : 1st group treated with distilled water and considered an control group (C) / the 2nd group treated with sesame oil ( T1) / 3rd group was givin hexavalent chromium ( 1000 ppm ) (T2) / 4th group treated with vitamin A ( 10 mg / kg ) and exposed to hexavalent chromium ( 1000 ppm ) (T3) / 5th group treated with vitamin A ( 10 mg kg ) (T4) . The expermint lasted 35 day . the results showed a significant ( P ? 0.05 ) decrease in avearage testis weight and sexual glan
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Autorías: Nadeema Badr Mohammed, Missaa Nadem, Huda Badwe Shbeeb, Iqbal Abdul Hussein Neamah, Najlaa Abbas AL Zuhairi, Nihad Mohammed Alwan. Localización: Retos: nuevas tendencias en educación física, deporte y recreación. Nº. 63, 2025. Artículo de Revista en Dialnet.
The research aims to measure the relationship and the impact of knowledge management processes to achieve the performance of insurance service, as well as analysis of the reality of the National Insurance Company to identify the level of overall performance, and to achieve this goal, it has been the selection of knowledge management processes according to the survey prepared a supplement to the study (Qubaisi, 2002), and of the four operations (knowledge generation, and storage of knowledge, and the distribution of knowledge, and application of knowledge), which represented the independent variable, and the performance has been the use of quantitative and qualitative measures, (sales growth, customer satisfaction), which represented the
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Purpose: This research seeks to provide a point of view based on the creation of sustainable value to the customer of the banks in the context of total quality management and relationship marketing. It aims to develop a model to measure the value of sustainable customer peduncular under total quality management PAL (administrative leadership, involvement of employees, continuous improvement, process improvement, staff training), through the mediation of relationship marketing and objective dimensions (administrative leadership, involvement of employees, continuous improvement, improving processes , staff training), and to explore any of the variables and dimensions more influential in the creation of sustainable value to the cust
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Renal transplantation is a principal treatment option for end-stage kidney failure. Bone loss and fracture are serious complication of kidney transplantation, associated with morbidity and mortality. The pathogenesis of post transplantation bone loss is multifactorial and complex
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The research aimed to identify and build two specialized scales for cognitive load and mental stress and to identify the level of each of them among 110-meter steeplechase runners among youth, and to prepare a psychological counseling approach to reduce the level of cognitive load and mental stress among 110-meter steeplechase runners among youth, so that the two research hypotheses are that there are differences. There are statistically significant differences between the results of the pre- and post-tests of the experimental group in measuring cognitive load. There are statistically significant differences between the results of the pre- and post-tests of the experimental group in measuring mental stress. The experimental method w
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This study aimed at examining the role played by the media outlets during the coverage
of the presidential election campaigns 2020 of the United States of America.
The analytical study used through a partial inventory of the research community
for almost three months from the announcement of the candidates’ names by
the major parties on August 13 to November 6، which is the official election day in
the U.S. National Public Radio Station (NPR) to achieve the objectives of the study.
The study reached a number of conclusions related to the contents، methods and
sources of media coverage of the election campaigns of the 2020 U.S. at the mentioned
station، where the researcher proposed a number of recommendations